code: def testConstantInput(self):
      # Define input vector, i.e. the autocorrelation vector
      onesInput = ones(1024)
      constantHarmonics = PercivalEnhanceHarmonics()(onesInput)
      # This code stores reference values in a file for later loading.
      save("constantharmonics.npy", constantHarmonics)
  
      # Reference samples are loaded as expected values
      expectedConstantHarmonics = load(
          join(filedir(), "percival/constantharmonics.npy")
      )
      expectedConstantHarmonicsList = expectedConstantHarmonics.tolist()
      self.assertEqualVector(
          constantHarmonics, expectedConstantHarmonicsList
      )
  
file_path: essentia/test/src/unittests/rhythm/test_percivalenhanceharmonics.py
imports: from numpy import *
  from essentia_test import *
  from essentia.standard import MonoLoader, PercivalEnhanceHarmonics
  from math import sin, pi
label_desc: Use image node_id 4 for calling the TestPercivalEnhanceHarmonics obj's underlying member method code with example usage: obj.testConstantInput() without return types